Conventionally, a process for producing fatty alcohols by catalytically hydrogenating fatty esters of methanol obtained by transesterification of glyceride with methanol is used in the industrial production of fatty alcohols. Alternatively, a method of catalytically hydrogenating wax esters obtained by esterification of fatty alcohols and fatty acids obtained by hydrolysis of glyceride, is also used. These two-stage processes are economically very favorable because valuable glycerin can be obtained with a high yield and high purity.
On one hand, the direct catalytic hydrogenation of glyceride enables an industrially important fatty alcohol product to be directly obtained from naturally occurring fats and oils, but is not so used in industrial production. This is because a side reaction wherein initially formed glycerin is hydrogenated on the surface of a catalyst occurs in the direct catalytic hydrogenation of glycerin, and thus glycerin cannot be obtained in a high yield, so the direct catalytic hydrogenation process cannot be economically favorable to the 2-stage process. This is one reason that the method of directly hydrogenating glyceride is not used on an industrial scale.
Methods of obtaining fatty alcohols by directly hydrogenating glyceride are described in for example U.S. Pat. Nos. 2,094,127, 2,109,844 and 2,241,417. DE-A 1668219 describes a method of hydrogenating glyceride obtained from fats and oils. U.S. Pat. Nos. 5,364,986 and 5,475,160 also describe methods of directly hydrogenating glyceride.